Stator pad assembly

ABSTRACT

A stator pad assembly includes a backing plate including a plate slot extending to a plate slot end, the backing plate carrying a stator lining including a lining slot extending to a lining slot end, the lining slot being generally positioned with a portion of the plate slot such that the plate slot end and the lining slot end are of similar position, and the plate slot defining a tool-engaging surface adapted to receive a tool to thereby cause the stator pad assembly to travel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/728,122, filed Sep. 7, 2018; U.S. Provisional Application No.62/728,285, filed Sep. 7, 2018; and U.S. Provisional Application No.62/728,448, filed Sep. 7, 2018, which are each incorporated herein byreference.

TECHNICAL FIELD

This invention relates to a stator pad assembly. More particularly, thisinvention relates to a stator pad assembly that includes a statorrelease slot and a tab.

BACKGROUND ART

To service a hydraulic caliper brake, it is generally necessary to pushback the pistons of the brake. This is typically a cumbersome andrelatively slow process. The common design for hydraulic caliper brakesprovides no particular feature to aid the service technician in pushingthe caliper pistons back. The typical method involves the use ofC-clamps, which is slow and awkward.

A second problem that is common in hydraulic calipers is removal andreinstallation of stator assemblies. Most designs require removal of thecaliper in order to accomplish removal and replacement of the statorassemblies. Handling of the stators is generally a problem, especiallyif the caliper is not removed. There is generally not an effective wayto get a hold of the stator. Again, this is also a slow process.

There are existing designs that do not require removal of the caliper,but the stators are hard to handle without removal of the caliper. Thesedesigns lack an effective manner for holding and manipulating thecomponents during removal and replacement.

Thus, there is a need for a stator assembly that offers one or moreimprovements over the prior art, such as ease of pushing a piston back.

SUMMARY OF THE INVENTION

In general, a stator pad assembly and corresponding methods areprovided. In accordance with an aspect of the invention, the stator padassembly may include a backing plate including a plate slot extending toa plate slot end, the backing plate carrying a stator lining including alining slot extending to a lining slot end, the lining slot beinggenerally positioned with a portion of the plate slot such that theplate slot end and the lining slot end are of similar position, and theplate slot defining a tool-engaging surface adapted to receive a tool tothereby cause the stator pad assembly to travel.

In accordance with another aspect of the invention, a method ofservicing a stator pad assembly may include providing a brake includinga housing having two pairs of torque pin holes, each pair of the torquepin holes receiving a respective torque pin, the torque pins carrying apair of stator pad assemblies, each of the stator pad assembliesincluding a respective backing plate with a plate slot, each of thestator pad assemblies adapted to be acted on by a respective pair ofpiston assemblies in normal operation of the brake, inserting a tool inone of the plate slots to thereby force the respective backing plateagainst the respective pair of piston assemblies, removing one of thetorque pins from the respective pair of torque pin holes, rotating atleast one of the pair of stator pad assemblies about the other of thetorque pins, and servicing the at least one of the pair of stator padassemblies that was rotated in the step of rotating.

It is an object of one aspect of the present invention to provide astator pad assembly allowing for ease of pushing a piston back withoutcomplicated tools or awkward motions.

It is an object of another aspect of the present invention to provide astator pad assembly, as above, that will allow for easy handling forremoval and reinstallation.

These and other objects of the present invention, as well as theadvantages thereof over existing prior art forms, which will becomeapparent from the description to follow, are accomplished by theimprovements hereinafter described and claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective front view of a stator pad assembly having arelease slot according to the concepts of the present invention.

FIG. 2 is a perspective rear view of the stator pad assembly accordingto the concepts of the present invention.

FIG. 3 is a perspective view of the opposed stator pad assemblies inposition with a caliper brake housing according to the concepts of thepresent invention.

FIG. 4 is a perspective view of the opposed stator pad assemblies inposition with the caliper brake housing, showing a tool in position inthe release slot for pushing back the piston according to the conceptsof the present invention.

FIG. 5 is a perspective view of the opposed stator pad assemblies inposition with the housing, showing each stator pad assembly rotated awayfrom the caliper brake housing according to the concepts of the presentinvention.

FIG. 6 is a perspective view of the caliper brake housing, spaced from awheel rotor according to the concepts of the present invention.

FIG. 7 is a perspective view of the opposed stator pad assemblies andcaliper brake housing in position with the wheel rotor according to theconcepts of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the Figures, a stator pad assembly according to theconcepts of the present invention is generally indicated by the numeral10. Stator pad assembly 10, which may also be described as statorassembly 10, includes a backing plate, generally indicated by thenumeral 12, which carries a stator lining, generally indicated by thenumeral 14, which may also be described as a stator pad 14. Stator pad14 may be secured to backing plate 12 by way of an adhesive or othergenerally known means, Installation and removal of stator pad 14 mayinclude utilizing integral molding holes 17 within backing plate 12.Integral molding holes 17 generally serve as anchor points for statorpad 14 material.

Backing plate 12 includes a slot 16 formed therein. Slot 16 may have afirst end within a tab 38 of backing plate 12, which will be furtherdescribed herein below with respect to the function of tab 38. Slot 16,which may also be referred to as release slot 16, may be formed in thecenter or the central portion of the width of backing plate 12. This maybe described as slot 16 being aligned with the centerline of a pair ofpiston assemblies 18, which may also be described as pistons 18. Arespective pair of piston assemblies 18 is provided for each statorassembly 10 and piston assemblies 18 are adapted to move stator assembly10 to a braking position by way of hydraulic fluid.

Slot 16 extends only into a portion of backing plate 12. That is to say,slot 16 does not extend entirely through the length of backing plate 12,such that slot 16 extends to an end 20 within backing plate 12. End 20may be a curved end, which may be in the particular shape of asemi-circle as shown in the Figures. In other embodiments, end 20 may berectangular or rectangular with corner radii or another suitable shape.As best seen in FIGS. 3 and 4, and as will be discussed further hereinbelow, a pair of opposed stator pad assemblies 10 may be utilized, suchthat slot 16 from one stator assembly 10 faces inward toward slot 16 ofthe other stator assembly 10.

In a corresponding position as end 20 and a lower portion of slot 16,stator lining 14 includes a slot 22 formed therein. Slot 22 may beformed in the center or the central portion of the width of statorlining 14. This may be described as slot 16 being formed in thecenterline of the pair of piston assemblies 18. Slot 22 extends onlyinto a portion of stator lining 14. That is to say, slot 22 does notextend entirely through the length of stator lining 14, such that slot22 extends to an end 24 within stator lining 14. End 24 may be a curvedend, which may be in the particular shape of a semi-circle. In otherembodiments, end 24 may be rectangular or rectangular with corner radiior another suitable shape. As best seen in FIGS. 3 and 4, in the pair ofstator assemblies 10, slot 22 from one stator assembly 10 faces inwardtoward slot 22 of the other stator assembly 10.

In one or more embodiments, end 24 may be of the same or similar shapeas end 20. That is to say, end 24 may aligned or substantially alignedwith end 20. This may be useful for providing a constant surface forcontacting a distal end of a tool 26 with the constant surface, as willbe further discussed herein below.

End 24 of slot 22 may include a central wear slot 42 extendingtherefrom, which slot 42 is useful for knowing the condition of statorlining 14, as further discussed below. Central wear slot 42 with slot 22together extend entirely through the length of stator lining 14. Though,as mentioned above, slot 22 itself does not extend entirely through thelength of stator lining 14. It should be readily appreciated that slot22 is of a different shape than the central wear slot 42.

A pair of opposed stator pad assemblies 10 may be particularly suitablefor use with a caliper brake, generally indicated by the numeral 30,including piston assemblies 18. Caliper brake 30 is adapted to providebraking function to a wheel rotor 36, which is part of a wheel endassembly, which is generally indicated by the numeral 44. Caliper brake30 may be mounted to wheel end assembly 44 by way of bolts 46.

In the configuration of caliper brake 30, when stator assemblies 10require servicing, it is generally necessary to push back the respectivepair of piston assemblies 18 with which stator assembly 10 is coupled.That is, stator assembly 10 needs to be moved toward the respective pairof piston assemblies 18.

To achieve this movement of stator assembly 10, a user may utilize tool26, which may be a screwdriver or crow bar or other suitable implement.A first end of tool 26 may be inserted into slot 16 and slot 22. Tool 26may be inserted until a distal end thereof contacts end 20 and/or end24. Slot 16 may be said to define a tool-engaging surface 28 in backingplate 12. The user of tool 26 may contact tool 26 with tool-engagingsurface 28 when tool 26 is inserted into slot 16 and slot 22. Upon tool26 contacting tool-engaging surface 28, the user causes tool 26 to applysufficient force on tool-engaging surface 28 to thereby cause statorassembly 10 to move against the pair of piston assemblies 18. Thisthereby pushes back the pair of piston assemblies 18.

As suggested above, slot 16 and slot 22 are centrally located in therespective components. Thus, the force of tool 26 also acts centrally onthe pair of piston assemblies 18. Advantageously, this causes consistentmovement of piston assemblies 18 and avoids cocking piston assemblies 18and otherwise damaging piston assemblies 18 and respective componentsthereof.

For servicing stator assemblies 10 of caliper brake 30, the hydraulicpressure normally supplied to caliper brake 30 is deactivated. Thus, theforce of tool 26 against stator assemblies 10 is able to push back therespective piston assembly 18. This may also release any hydraulicpressure that may remain when caliper brake 30 is in the deactivatedstate. Once stator assemblies 10 move the respective piston assembly 18by tool 26 as discussed above, piston assemblies 18 will remain in thatposition because no further hydraulic pressure is being supplied in thismode of caliper brake 30.

Caliper brake 30 includes a pair of torque pins 32 for securing statorassemblies 10 within a caliper brake housing 33, which may also bereferred to as housing 33. For servicing stator assemblies 10 oncepiston assemblies 18 are moved, one of the torque pins 32 may be removedfrom the respective torque pin holes 34 of stator assemblies 10 and therespective torque pin holes 35 within housing 33. This may also includeremoving a respective spring 37 positioned around torque pin 32 andbetween the pair of stator assemblies 10.

Stator assemblies 10 may then be rotated about the other torque pin 32(and spring 37) that remains within caliper housing 33. Statorassemblies 10 may be rotated away from caliper housing 33 of caliperbrake 30 such that they can be accessed by a user for performingmaintenance thereon. This maintenance may include replacing statorlinings 14. In other embodiments, both of the torque pins 32 and both ofthe springs 37 may be removed to completely remove stator assemblies 10from caliper brake 30.

Once maintenance of stator assemblies 10 is completed, stator assemblies10 may be reassembled with caliper brake 30 in a reverse manner asdescribed above, which includes reactivating the hydraulic pressure topiston assemblies 18. In this normal, non-maintenance operation ofcaliper brake 30, a portion of wheel rotor 36 is positioned between thepair of stator assemblies 10.

As suggested above, for assisting with ease of servicing statorassemblies 10, backing plate 12 may include tab 38 as an extension ofbacking plate 12. Tab 38 may particularly extend from a central positionwith respect to the width of backing plate 12. As discussed above, tab38 includes a portion of slot 16, including a distal end of slot 16.

Tab 38 protrudes from backing plate 12 and extends far enough frombacking plate 12 as to be outside of an outer perimeter of caliperhousing 33 of brake 30, as perhaps best seen in FIG. 7. This extensionof tab 38 outside of caliper housing 33 enables tab 38 to be easilygrabbed by a user for rotation and/or removal of stator assemblies 10.For additional ease, caliper housing 33 may include a slot 40, which mayalso be described as a depression 40, generally corresponding to theposition of tab 38, such that tab 38 serves as an even longer extensionfrom caliper housing 33.

For assisting a user with knowing when stator assemblies 10 needservicing, stator lining 14 may include one or more wear slots 42 formedtherein. Any suitable number of wear slots 42 may be utilized. Statorassemblies 10 of brake 30 include three wear slots 42—a central wearslot, and one wear slot on each side of stator lining 14.

As shown in FIG. 1, slots 42 may extend all the way through the heightor length of stator lining 14. In other embodiments, slots 42 do notextend all the way through the height or length of stator lining 14. Asshown in FIG. 1, slots 42 may not extend all the way through the depthor thickness of stator lining 14. In other embodiments, slots 42 doextend all the way through the depth or thickness of stator lining 14.Slots 42 are shown as linear shaped, but other suitable configurationsmay be utilized. Though, slot 22 is adapted to receive tool 26, slots 42are generally too narrow to fit tool 26.

In operation of caliper brake 30, stator linings 14 will wear and becomeless thick. Thus, slots 42 will become less deep. During operation ofcaliper brake 30, slot 42 will be worn from its original depth to asubsequent depth. Slots 42 may be designed for a particular depth, suchthat a user will be able to identify, based on the subsequent depth,that stator linings 14 should be replaced. Stator linings 14 can bereplaced by a user upon this identification. Slots 42 may also behelpful for controlling vibration and noise of caliper brake 30.

It is thus evident that a stator pad assembly constructed as describedherein accomplishes the objects of the present invention and otherwisesubstantially improves the art.

What is claimed is:
 1. A stator pad assembly comprising: a backing plateincluding a plate slot extending to a plate slot end, the backing platecarrying a stator lining including a lining slot extending to a liningslot end, the lining slot being generally positioned with a portion ofthe plate slot such that the plate slot end and the lining slot end areof similar position, and the plate slot defining a tool-engaging surfaceadapted to receive a tool to thereby cause the stator pad assembly totravel.
 2. The stator pad assembly of claim 1, the backing plate havinga width with a plate central portion, the plate slot formed in the platecentral portion, and the stator lining having a width with a liningcentral portion, the lining slot formed in the plate central portion. 3.The stator pad assembly of claim 2, the plate slot end being of a shapeselected from the group consisting of semi-circle, rectangular, andrectangular with corner radii, and the lining slot end being of a shapeselected from the group consisting of semi-circle, rectangular, andrectangular with corner radii.
 4. The stator pad assembly of claim 1,the stator lining including a wear slot.
 5. The stator pad assembly ofclaim 4, the wear slot extending centrally from the lining slot end. 6.The stator pad assembly of claim 5, the stator lining having a length,the stator pad assembly further comprising an additional wear slotextending through the entirety of the length of the stator lining. 7.The stator pad assembly of claim 1, the backing plate including a tabextending therefrom, and the tab including a portion of the plate slotbut not including the plate slot end.
 8. The stator pad assembly ofclaim 7, the stator pad assembly positioned within a brake housinghaving an outer perimeter, and the tab extending beyond the outerperimeter of the brake housing.
 9. The stator pad assembly of claim 8,the housing including a housing slot generally corresponding to theposition of the tab.
 10. A method of servicing a stator pad assembly,the method comprising: providing a brake including a housing having twopairs of torque pin holes, each pair of the torque pin holes receiving arespective torque pin, the torque pins carrying a pair of stator padassemblies, each of the stator pad assemblies including a respectivebacking plate with a plate slot, each of the stator pad assembliesadapted to be acted on by a respective pair of piston assemblies innormal operation of the brake, inserting a tool in one of the plateslots to thereby force the respective backing plate against therespective pair of piston assemblies, removing one of the torque pinsfrom the respective pair of torque pin holes, rotating at least one ofthe pair of stator pad assemblies about the other of the torque pins,and servicing the at least one of the pair of stator pad assemblies thatwas rotated in the step of rotating.
 11. The method of claim 10, furthercomprising removing the other of the torque pins such that the pair ofstator pad assemblies can be entirely removed from the housing.
 12. Themethod of claim 10, wherein each backing plate includes a stator lininghaving a wear slot having an original depth, further comprising a stepof identifying that the wear slot of at least one of the stator liningshas worn from the original depth to a subsequent depth, such that thestator lining having the wear slot at the subsequent depth is thereby ina condition needing maintenance.
 13. The method of claim 12, wherein thestep of servicing includes replacing the stator lining having the wearslot at the subsequent depth.
 14. The method of claim 10, wherein thestep of servicing includes replacing the stator lining of the at leastone of the pair of stator pad assemblies that was rotated in the step ofrotating.
 15. The method of claim 10, wherein each of the backing platesincludes a respective tab, and wherein the step of rotating includesgrasping the tab of the at least one of the pair of stator padassemblies to thereby cause the rotating.